OBJECTIVE: To establish the optimal level of dietary iron for the pregnant rhesus monkey to ensure against the development of iron-deficiency anemia (IDA) in her infant. RESULTS Monkey chow diets containing 145 or 205 ppm iron were insufficient in reducing the incidence of IDA in pregnant females and their infants. Appropriate levels of trace minerals, such as iron, are critical for the normal development of a number of physiological systems, including the immune and central nervous systems. A subset of infant monkeys have been found to manifest signs of IDA, when born to females who consumed standard monkey chow diets while pregnant. This anemia emerges between 2-6 months of age, and appears to reflect a low transplacental transfer of maternal iron stores to the fetus. The purpose of the current study was to evaluate the beneficial aspects of iron supplementation on the gravid female. Chow with two levels of iron fortification were tested 145 ppm (standard), and 205 ppm (+60). Iron supplementation (+60) was insufficient to significantly improve maternal or infant hematological profiles. Because a poor hematological profile in the infant is associated with lower immune responses, it is critical to establish the optimal dietary regime that meets the needs of the pregnant female. FUTURE DIRECTIONS We plan to study another small group of females that will be provided with 145 ppm of iron in their chow to determine if it will be efficacious in preventing the development of IDA. KEY WORDS anemia, immune, diet, Macaca mulatta